In the dispensing of soft drinks from fountain heads and the like, a constant problem is the assurance that a full measure of beverage is dispensed into the cup or other container, without the overflowing of beverage over the lip of the cup and down the side thereof. When the level of the beverage within the cup is not within a reasonable distance from the top of the cup, the customer feels that he has been shorted. In like manner, when the beverage is allowed to overrun the cup, not only is expensive waste experienced, but the cup itself may become wet or sticky and, therefore, unsatisfactory to the customer.
Present soft drink dispensers often include measuring devices, measuring either the actual volume of beverage dispensed, or the timing of the dispensing cycle, to assure that a full measure has been dispensed. However, if the operator has placed too much, or too little ice within the cup, the same problems of overflowing or apparent shortages may occur. Similarly, if the customer requests no ice, light ice, or heavy ice, systems which assure the dispensing of a fixed volume of beverage will again result in either apparent shortages or overflows.
Various attempts have been taken in the past to monitor the filling of a cup from a soft drink dispenser to assure the dispensing of a full measure, without objectionable overflow. Consideration has been given to the use of sonic devices or proximity transducers for such systems, but without success. Further, dispensing systems have been configured with probes extending into the cup, or along the side thereof, to shut off the beverage flow instantly upon the sensing of an overflow situation. Such devices, however, raise issues of sanitation problems, since the probes themselves become coated with beverage and syrup, giving rise to a sticky or gummy device which is inserted into a customer's cup. Further, many such units do no prevent an overflow, but actually sense the overflow, terminating dispensing to prevent excessive overflow.
The prior art is devoid of a reliable, durable, and sanitary system which is operative to sense and monitor the actual level of beverage within a container or cup and to terminate the flow of such beverage at a point assuring a full measure of beverage without overflow.